Sounds like Jaeger's design as found in a circa 1910/1911 catalogue here, http://www.germanguns.com/books/R013.html , which would make a good pairing along with a GGCA membership, that is if you aren't already a member. Somewhere I picked up the term for the muzzle crosshatching as a menancing muzzle.

Kind Regards,

Raimey
rse